1 files changed, 33 insertions, 0 deletions
diff --git a/meta-arm/meta-arm-bsp/recipes-kernel/linux/linux-yocto-6.5/n1sdp/0005-arm64-kpti-Whitelist-early-Arm-Neoverse-N1-revisions.patch b/meta-arm/meta-arm-bsp/recipes-kernel/linux/linux-yocto-6.5/n1sdp/0005-arm64-kpti-Whitelist-early-Arm-Neoverse-N1-revisions.patch
new file mode 100644
index 0000000000..42ef0ee38a
--- /dev/null
+++ b/meta-arm/meta-arm-bsp/recipes-kernel/linux/linux-yocto-6.5/n1sdp/0005-arm64-kpti-Whitelist-early-Arm-Neoverse-N1-revisions.patch
@@ -0,0 +1,33 @@
+From a9df434f077e7f1d8895e76381ba7179f3ebb1ba Mon Sep 17 00:00:00 2001
+From: Andre Przywara <andre.przywara@arm.com>
+Date: Fri, 17 May 2019 17:39:27 +0100
+Subject: [PATCH] arm64: kpti: Whitelist early Arm Neoverse N1 revisions
+
+Early revisions (r1p0) of the Neoverse N1 core did not feature the
+CSV3 field in ID_AA64PFR0_EL1 to advertise they are not affected by
+the Spectre variant 3 (aka Meltdown) vulnerability.
+
+Add this particular revision to the whitelist to avoid enabling KPTI.
+
+Signed-off-by: Andre Przywara <andre.przywara@arm.com>
+Change-Id: I78df055a3e674aefd195d41cc6dc4ee08b0af099
+Upstream-Status: Inappropriate
+Signed-off-by: Andre Przywara <andre.przywara@arm.com>
+Signed-off-by: Vishnu Banavath <vishnu.banavath@arm.com>
+Signed-off-by: Adam Johnston <adam.johnston@arm.com>
+---
+ arch/arm64/kernel/cpufeature.c | 1 +
+ 1 file changed, 1 insertion(+)
+
+diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
+index 2c0b8444fea6..5c0ff40c6c8b 100644
+--- a/arch/arm64/kernel/cpufeature.c
++++ b/arch/arm64/kernel/cpufeature.c
+@@ -1690,6 +1690,7 @@ static bool unmap_kernel_at_el0(const struct arm64_cpu_capabilities *entry,
+ 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_2XX_SILVER),
+ 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_3XX_SILVER),
+ 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_4XX_SILVER),
++		MIDR_REV(MIDR_NEOVERSE_N1, 1, 0),	/* missing CSV3 */
+ 		{ /* sentinel */ }
+ 	};
+ 	char const *str = "kpti command line option";